Radiant cooling and/or heating assembly

ABSTRACT

A radiant cooling/heating assembly includes a housing ( 15, 216 ) containing a heat transfer pipe ( 20, 67, 80, 120, 226, 316 ) through which a heat transfer medium is passable, at least one outer radiant heat transfer surface ( 50, 74, 87, 150, 213   a,    213   b,    313   a,    313   b ) for heat transfer with the surrounding environment, a first heat transfer panel ( 30, 68, 81, 130, 230, 326 ) with a first inner heat transfer surface ( 52, 152 ), and a second heat transfer panel ( 16, 116, 228, 324 ) with a second inner heat transfer surface ( 51, 151 ) which faces the first inner heat transfer surface, the first heat transfer panel in contact with part of the heat transfer pipe, the first inner heat transfer surface and the second inner heat transfer surface separated from each other by a separation ( 55, 73, 86, 156, 236, 332 ) which is filled at least partly with a carbon layer or coating.

FIELD OF THE INVENTION

The present invention is directed to a radiant heat transfer apparatus for use with a radiant cooling and/or heating system. More particularly, the present invention is directed to a radiant cooling and/or heating assembly for such a system suitable for use in indoor or outdoor environments. For conciseness, the term “cooling/heating” will hence forth in this document mean “cooling and/or heating”.

BACKGROUND OF THE INVENTION

Radiant cooling provides cooling by absorbing the heat radiated from objects within a confined space, for instance, an indoor space with a ceiling and a floor. A radiant cooling system is usually implemented as a series of flat panels and can either be installed on ceilings, walls or the floor. Radiant cooling systems have been embedded in the ceilings of adobe homes, taking advantage of the thermal mass to provide a uniform and steady cooling effect. When used on the floor, it is often referred to as radiant floor cooling. Typically, a radiant cooling system used for homes features an array of interconnected cooling panels at the ceiling.

Although radiant cooling is potentially suitable for use in arid climates, radiant cooling can be problematic for homes in more humid climates in which condensation is prone to be formed on surfaces of radiant cooling panels. Once the surface temperature is cooled beyond the dew point of air, that is, the temperature to which air must be cooled to become saturated with water vapor, the moisture in the air condenses, causing water droplets to form on the panel surfaces. With condensation on the surfaces, the effectiveness of the cooling panels is adversely affected as the condensation insulates the air from direct contact with the panel surface.

Known radiant cooling applications have been based on aluminum panels suspended from the ceiling, through and within which chilled water is circulated. To be effective, the panels must be maintained at a temperature very near the dew point within the house, and the house must be kept dehumidified. In humid climates, simply opening a door could allow enough humidity into the home to allow condensation to occur.

In particular, subtropical and tropical regions typically have a relative humidity of 90% to 100% with a relatively higher dew point than those of non-tropical regions, which exacerbates the condensation problem and dramatically limits the cooling efficiency of the cooling panels. In all but the most arid locations, an auxiliary air-handling unit system would be required to keep the home's humidity low, adding further to the capital cost.

Similarly, there is also a need for radiant heating assemblies with improved heat transfer capability.

SUMMARY OF THE INVENTION

Accordingly, it is one of the objectives of the present invention to provide a radiant cooling/heating assembly for use with radiant cooling/heating systems that at least reduces the formation of condensation on the assembly's surface, hence enhancing heat transfer and dissipation in premises implemented with the radiant cooling/heating assemblies according to the present invention.

It is also an objective of the present invention to improve manufacturing and overall construction of radiant cooling/heating assemblies for achieving better overall cooling/heating performance and efficiency, as well as the providing ease of manufacturing of such assemblies.

These and other objectives are attained by the present invention pertaining to a radiant cooling/heating assembly including a general housing which houses a base panel supporting a meandering heat transfer pipe. The base panel provides one inner radiant surface which interfaces with an inner side of the housing. The housing provides at least one outer radiant surface arranged to face the heat source directly. The heat emitted from the heat source radiates to the outer radiant surface and is subsequently transmitted to the base panel. A heat transfer media is fed through the heat transfer pipe, preferably at a predetermined flow rate. In the case of a radiant cooling assembly intended for lowering the temperature of the surrounding environment, the heat transfer media has a lower temperature than the surrounding environment, such as chilled water. On the other hand, in the case of a radiant heating assembly intended for raising the temperature of the surrounding environment, the heat transfer media has a higher temperature than the surrounding environment, such as heated water.

In the case of a cooling assembly, as the heat transfer media travels through the heat transfer pipe, it carries away the heat absorbed by the inner and outer radiant surfaces, thus lowering the temperature of the surrounding environment. In particular, an air gap or an infill material such as graphite, of a predetermined gap width/thickness is provided within the radiant panel, setting an empty space between the inner and outer radiant surfaces for facilitating suppression of condensation. The internal of the radiant cooling panel is filled with insulation material for minimizing heat loss. The radiant cooling assemblies are adapted for absorbing heat from heat sources such as but not limited to ambient air, human occupants and appliances. The separation has a thickness 0.3 mm to 20 mm, fully or partially filled with a special infill heat transfer substance, such as graphite.

In the alternative case of a heating assembly, as the heat transfer media travels through the heat transfer pipe, it releases heat through the inner and outer radiant surfaces, thus raising the surrounding temperature. In particular, an air gap or an infill material such as graphite, of a predetermined gap width/thickness is provided within the radiant heating assembly, setting an empty space between the inner and outer radiant surfaces. The radiant heating assemblies are adapted for releasing heat to the surrounding environment, such as the ambient air, human occupants and appliances. The gap has a thickness 0.3 mm to 20 mm, fully filled or partially filled with a special infill heat transfer substance, such as graphite.

According to a first aspect of the present invention, there is provided a radiant cooling/heating assembly including a housing containing a heat transfer pipe through which a heat transfer media is passable, at least one outer radiant heat transfer surface for heat transfer with the surrounding environment, a first heat transfer panel with a first inner heat transfer surface, and a second heat transfer panel with a second inner heat transfer surface which faces said first inner heat transfer surface of said first heat transfer panel, wherein said first heat transfer panel is in contact with at least part of said heat transfer pipe, wherein said first inner heat transfer surface and said second inner heat transfer surface are separated from each other by a separation, and wherein said separation is filled at least partly with a thermal conductive layer made of at least one material having a thermal conductivity higher than that of air.

According to a second aspect of the present invention, there is provided a cooling/heating system including a heat exchanger and/or a boiler connected with at least one radiant cooling/heating assembly, said radiant cooling/heating assembly including a housing containing a heat transfer pipe through which a heat transfer media is passable, at least one outer radiant heat transfer surface for heat transfer with the surrounding environment, a first heat transfer panel with a first inner heat transfer surface, and a second heat transfer panel with a second inner heat transfer surface which faces said first inner heat transfer surface of said first heat transfer panel, wherein said first heat transfer panel is in contact with at least part of said heat transfer pipe, wherein said first inner heat transfer surface and said second inner heat transfer surface are separated from each other by a separation, and wherein said separation is filled at least partly with a thermal conductive layer made of at least one material having a thermal conductivity higher than that of air.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 a is a schematic view of a radiant cooling/heating system incorporating a number of radiant cooling/heating assemblies in accordance with the present invention;

FIG. 1 b is a schematic view of a connection for heat exchanger suitable for use in the radiant cooling/heating system of FIG. 1 a;

FIG. 1 c is a schematic view of a connection for water pump suitable for use in the radiant cooling/heating system of FIG. 1 a;

FIG. 1 d is a schematic view of a connection of a number of radiant cooling/heating assemblies according to the present invention suitable for the radiant cooling/heating system of FIG. 1 a;

FIG. 1 e is a schematic view of a connection for a primary air handling unit/air handling unit (PAU/AHU) suitable for use in the radiant cooling/heating system of FIG. 1 a;

FIG. 1 f show descriptions of the legends used in FIGS. 1 a to 1 e;

FIGS. 2 a and 2 b illustrate the general construction of radiant panels according to a first embodiment of the present invention and suitable for use in the system of FIG. 1 a;

FIG. 3 illustrates the internal components of the radiant panel of FIGS. 2 a and 2 b;

FIG. 4 illustrates the detailed construction of a part of the radiant panel of FIGS. 2 a and 2 b;

FIG. 5 is a section view illustrating the internal arrangement of the radiant panel of FIGS. 2 a and 2 b;

FIG. 6 a is a top view of a radiant panel according to a second embodiment of the present invention;

FIG. 6 b is an inside view of the radiant panel of FIG. 6 a;

FIG. 6 c is a front view of the radiant panel of FIG. 6 a;

FIG. 6 d is a sectional view taken along the line A-A of FIG. 6 b;

FIG. 6 e is an enlarged view of the encircled part marked “G” in FIG. 6 d;

FIG. 6 f is a sectional view taken along the line X-X of FIG. 6 c;

FIG. 6 g is a sectional view taken along the line Y-Y of FIG. 6 c;

FIG. 6 h is a side view of the radiant panel of FIG. 6 a;

FIG. 6 i is a sectional view taken along the line B-B of FIG. 6 b;

FIG. 6 j is an enlarged view of the encircled part marked “H” in FIG. 6 i;

FIG. 7 a is a top view of a radiant panel according to a third embodiment of the present invention;

FIG. 7 b is an inside view of the radiant panel of FIG. 7 a;

FIG. 7 c is a front view of the radiant panel of FIG. 7 a;

FIG. 7 d is a sectional view taken along the line A-A of FIG. 7 b;

FIG. 7 e is a sectional view taken along the line X-X of FIG. 7 c;

FIG. 7 f is a sectional view taken along the line Y-Y of FIG. 7 c;

FIG. 7 g is a side view of the radiant panel of FIG. 7 a;

FIG. 7 h is a sectional view taken along the line B-B of FIG. 7 b;

FIG. 8 is a schematic view showing a first radiant surface and a second radiant surface generally facing each other for the purpose of illustrating the calculation of the radiation from the first radiant surface to the second radiant surface;

FIG. 9 a shows the construction of a radiant panel according to a fourth embodiment of the present invention;

FIG. 9 b shows the interior construction of the radiant panel of FIG. 9 a;

FIG. 9 c shows a sectional view of the radiant panel of FIG. 9 a;

FIG. 9 d is an enlarged view of the encircled part marked “J” in FIG. 9 c;

FIG. 10 shows an infrared image taken on an array of radiant panels showing thermal readings and uniformity;

FIG. 11 a shows a top view of a radiant cooling/heating assembly according to a fifth embodiment of the present invention;

FIG. 11 b shows a bottom panel of the radiant cooling/heating assembly of FIG. 11 a;

FIG. 11 c shows a sectional view of the cooling/heating assembly taken along the line A-A of FIG. 11 a;

FIG. 11 d is an enlarged view of the encircled part marked “C” in FIG. 11 c;

FIG. 11 e is an enlarged view of the encircled part marked “D” in FIG. 11 d;

FIG. 11 f shows a sectional view of the cooling/heating assembly taken along the line B-B of FIG. 11 a;

FIG. 12 a shows a top view of a radiant cooling/heating assembly according to a sixth embodiment of the present invention;

FIG. 12 b shows a bottom panel of the radiant cooling/heating assembly of FIG. 12 a;

FIG. 12 c shows a sectional view of the cooling/heating assembly taken along the line A-A of FIG. 12 a;

FIG. 12 d is an enlarged view of the encircled part marked “E” in FIG. 12 c;

FIG. 12 e is an enlarged view of the encircled part marked “F” in FIG. 12 d ; and

FIG. 12 f shows a sectional view of the cooling/heating assembly taken along the line B-B of FIG. 12 a.

The figures herein are for illustrative purposes only and are not necessarily drawn to scale.

DETAILED DESCRIPTION OF THE EMBODIMENTS

The following clearly and completely describes the technical solutions in the embodiments of the present invention with reference to the accompanying drawings. It should of course be understood that the described embodiments are merely some but not all of the embodiments of the present invention. All other embodiments based on the embodiments of the present invention and obtained by a person of ordinary skill in the art without investing creative efforts shall fall within the scope of the present invention.

Unless otherwise specifically provided, all measurements are made in metric units. It is understood that unless otherwise specifically noted, the materials compounds, chemicals, etc. described herein are typical commodity items and/or industry-standard items available from a variety of suppliers worldwide.

FIGS. 1 a to 1 f show schematic views of a radiant cooling/heating system 100 and its sub-systems. The system 100 includes a boiler 101 for providing heating and/or a heat exchanger 102 for providing cooling, and multiple interconnected radiant panels 10. Each radiant panel 10 can either be connected to another radiant panel 10, or directly to the boiler 101 or the heat exchanger 102. The radiant cooling/heating system 100 may include a selector valve, for instance, a three-way valve, which allows selective connection between the radiant panels 10 and the boiler 101/heat exchanger 102. The selector valve allows for switching of operation mode between a heating mode, i.e., the radiant panels 10 being connected to the boiler 101, and a cooling mode, i.e., the radiant panels 10 being connected to the heat exchanger 102. Copper or aluminum tubes 105 and fittings are used for forming pathways between the radiant panels 10, the boiler 101 and the heat exchanger 102, although other types of tubes and fittings can be used as suitable substitutes. Specifically, the radiant cooling/heating system 100 is a closed system in which the pathways form a closed loop that allows fluids, such as heated water or chilled water, to circulate within the system 100 through the interconnected radiant panels 10. Radiant panels 10 according to an embodiment of the present invention, for effectuating radiant cooling/heating, will be described in conjunction with accompanied FIGS. 2 a to 5, whilst FIGS. 6 a-6 j , FIGS. 7 a-7 h , FIGS. 9 a-9 d , FIGS. 11 a-11 f and FIGS. 12 a-12 f illustrate manufacturing and constructional details of radiant cooling/heating assemblies according to various other embodiments of the present invention.

According to FIG. 2 a and FIG. 2 b , an exemplary embodiment of the radiant cooling panel 10 (hereinafter referred to as “radiant panel”) according to the present invention is shown. For ease of visualizing, each radiant panel 10 takes the shape of a square with a nominal dimension of, for instance, about 600 mm in length by 600 mm in width and with a nominal thickness of about 40 mm. Dimensions and thickness of the panels 10 may vary depending on deployment area, manufacturing constraints or other limitations. Although different shapes of the radiant panels 10 may be adopted for specific constructional implementation, tileable shapes are most preferred and essential for forming an “array” of panels 10 effectively covering a broad ceiling area, floor area or wall area. Generally, as shown in the figures, each radiant panel 10 has a functional side 11 (as shown in FIG. 2 a ), and a non-functional side 12 (as shown in FIG. 2 b ) which is simply the back side of the radiant panel 10. The functional side 11 provides a substantially flat surface covering a large or entire area of the functional side 11 of the radiant panel 10, whilst four lateral sides 13 surround the radiant panel 10 to define the thickness thereof.

The functional side 11, the non-functional side 12 and the four lateral sides 13 together define an assembly housing 15 for the radiant panel 10. The assembly housing 15 includes an outer housing portion 16 and a main housing portion 17 coupled thereto. Each radiant panel 10 further includes an inlet end 18 and an outlet end 19 for passage of a fluid media, such as water (not shown). The inlet end 18 and the outlet end 19 protrude outward from inside the radiant panel 10 such that they are exposed on the non-functional side 12 to facilitate installation. The inlet end 18 provides access to a heat transfer pipe 20 inside the radiant panel 10 for the fluid media, i.e., chilled water in the case of a radiant cooling assembly and hot water in the case of a radiant heating assembly, driven by the connected heat exchanger 102 or boiler 101. Preferably, if a chilled media is used with a heat exchanger in the system 100, the temperature of the chilled media is to be maintained at 5° C. to 12° C. for a most desirable radiant cooling effect. More preferably, when the radiant panels 10 are used for indoor radiant cooling, the indoor ambient temperature should be no higher than 28° C., and ideally within 20° C. to 28° C. Under the above temperature requirements, the radiant panels 10 according to the present invention provide effective radiant cooling while condensation on the radiant surface can be largely suppressed or at least minimized. For instance, the diameter of the heat transfer pipe 20 would be limited from about 8 mm to about 15 mm.

Referring to FIG. 3 and FIG. 4 , inside the panel housing 15 there lies a base panel 30 which provides general support for the meandering heat transfer pipe 20. For instance, the base panel 30 may be consisted of several elongated rectangular panel sections 32 lying adjacent to each other. Preferably, these panel sections 32 are made from a heat conductive metallic material, such as aluminum or copper, or any other suitable metal or alloy with good heat transfer characteristic. The panel sections 32 may be held together, i.e., side by side. In particular, conducting portions 33 may be provided on each of the panel sections 32 for facilitating direct contact of the panel sections 32 with the heat transfer pipe 20 for heat exchange purposes. Advantageously, each of the conducting portions 33 includes a concave surface 39 with a curvature complementary to that of the outer surface 21 of the heat transfer pipe 20. This specific arrangement serves to maximize the contact area between the heat transfer pipe 20 and the panel sections 32 and thus enhances heat transfer efficiency.

Preferably, the panel sections 32 may be made from black anodized aluminum extrusions. Each individual panel section 32 may be formed in rectangular strip with a uniform thickness of, for instance, about 2 mm. On one of the two lengthwise edges of each panel section 32 is provided the conducting portion 33. For instance, as shown in FIG. 4 , the conducting portion 33 may be a c-shaped flange 35 extending along the lengthwise edge. Preferably, the c-shaped flange 35 is formed integrally with the panel section 32 during the extrusion process of the panel section 32.

The panel sections 32 are arranged side by side with each other to form the base panel and the heat transfer pipe 20 extends over and meanders along above the base panel 30 in the manner as shown. In particular, the heat transfer pipe 20 includes multiple bent sections, each bent section may be a substantially U-shaped bend 22, i.e., “U-bend”, with a number of straight portions 23 between the U-shaped bends 22. According to the present embodiment as shown, the heat transfer pipe 20 has five U-bends 22 (two bends hidden by the open housing in FIG. 3 ) between the inlet end 18 and the outlet end 19, resulting in, for instance, six straight portions 23 lying parallel to each other on the base panel 30.

The conducting portion 33 of each of the panel sections 32 extends along the length of the straight portion 23 of the heat transfer pipe 20 and terminates at the beginning of the U-bend 22. This allows for clearance for the curved portion of the heat transfer pipe 20. As shown in FIG. 4 , the profile of the c-shaped flange 35 may be in semi-circular shape and may have a concave curvature which corresponds to that of the exterior of the heat transfer pipe 20. This serves to maximize the contact between the c-shaped flange 35 and the heat transfer pipe 20 for optimal heat transfer. Two adjacent panel sections 32 with oppositely arranged c-shaped flanges 35 surround the heat transfer pipe 20 and substantially cover the entire straight portion 23, with the straight portions 23 being held within the conducting portions 33. For instance, the panel sections 32 are arranged such that each of the six straight portions 23 of the heat transfer pipe 20 is surrounded by two c-shaped flanges 35. The number of bends, dimensions of the bends and the panel sections 32 may vary according to manufacturing limitations and practical technical requirements.

The panel sections 32 may be secured together by fastening means, including, but not limited to, for example, nylon straps, rivets or screws, or spot welding, etc. Advantageously, as shown in FIG. 3 and FIG. 5 , flexible cable straps 36 are used for securing between the panel sections 32. For example, small holes 34 are provided on the panel section 32 at positions immediate to the c-shaped flange 35, and the cable strap 36 is then inserted through the hole 34 on a first panel section 32, extended around both the c-shaped flanges 35 of the first panel section 32 and the adjacent second panel section 32, then through the other small hole 34 provided on the second panel section 32. The cable strap 36 is then latched and tensioned, forcing the first and second panel sections 32 against each other with the heat transfer pipe 20 biased in between by the two c-shaped flanges 35. Preferably, more than one set of holes 34 may be provided on each of the panel sections 32 along the c-shaped flange 35. For instance, at least one set of holes 34 may be provided near each end of the c-shaped flange 35 as shown, although more may also be provided to achieve a more evenly distributed biasing force being applied on the heat transfer pipe 20. The added biasing force by the tension of the cable straps 36 facilitates the contact between the outer surface of the heat transfer pipe 20 and the c-shaped flanges 35, hence providing enhanced heat transfer from the heat transfer pipe 20 to the panel sections 32, or vice versa. As an alternative, those skilled in the art may also consider using metallic wires, for instance, copper wires, as a substitute for cable straps.

Preferably, the base panel 30 is bounded by frame members 41 at each of the four lateral edges. The frame members 41 constitute a peripheral frame 40 for the entire base panel 30. Preferably, each of the frame members 41 extends along a lateral side of the base panel 30 and includes a positioning slot 42 for accommodating the thickness of base panel 30. The frame members 41 serve also as stiffeners for the base panel 30 such that the base panel 30 can be maintained substantially flat and even throughout its span. Overall, the peripheral frame 40 provides added rigidity against warping or bending of the base panel 30. For instance, the frame members 41 may be formed by injection molding using nylon resin or the like. As shown in FIG. 5 , the frame member 41 has a cross-sectional profile of an “F” shape, having a positioning slot 42 between a first support portion 43 and a second support portion 44. The frame members 41 are shown as being secured to the assembly 10 by screws 25.

The panel housing 15 of the radiant panel 10 encloses the base panel 30 and heat transfer pipe 20. Referring to FIG. 5 , the panel housing 15 includes the outer housing portion 16, and the main housing portion 17 arranged for coupling thereto. For instance, coupling flanges 48 may be provided around the peripheral edges of the outer housing portion 16 for facilitating the assembling and sealing of the two housing portions once coupled. An external side of the outer housing portion 16 provides an outer radiant surface 50 substantially covering the entire functional side 11. The base panel 30 includes an inner radiant surface 52 on its underside lying opposite to an inner side 51 of the outer housing portion 16. The second radiant surface 52 on the base panel 30 should ideally be a flat or a substantially flat surface. As shown, an empty space 55 is formed between the base panel 30 and the outer housing portion 16 when the base panel 30 is coupled to the outer housing portion 16. Essentially, the empty space 55 provides an air gap 56 between the inner radiant surface 52 and the inner side 51 of the first housing portion 16, thus acting as a separation which separates the base panel 30 and the outer housing portion 16.

Preferably, the air gap 56 would have a constant or substantially constant gap width throughout the empty space 55. Practically, the gap width would be affected by the alignment and levelness of the base panel 30 with respect to the outer housing portion 16, and the degree of warping of the outer housing portion 16 due to the inherent flexibility of sheet metal. For instance, the outer housing portion 16 would have a thickness of at least 0.5 mm, although a higher thickness is more preferable. The outer housing portion 16 may have a thickness of up to 3 mm for providing desirable rigidity.

The support portions 44 of the frame members 41 provide support for the outer housing portion 16 and ensure that the outer housing portion 16 stays a certain distance, i.e., the gap width, from the base panel 30. Once coupled to the outer housing portion 16, the support portions 44 abut against an inner surface 51 of the outer housing portion 16 and serve to maintain the air gap 56 between the inner radiant surface 52 of the base panel 30 and the inner surface 51 of the outer housing portion 16. While the support portions 44 can provide the supports at the peripheral edges of the base panel 30, additional supports may be used to provide support at locations distant from the peripheral edges. For example, a center support member (not shown) may be used to support the center portion of the base panel 30. These additional supports effectively maintain the gap width and minimize the variation of the gap width throughout the span of the entire panel 10. Sealing arrangement may be provided between the base panel 30 and the outer housing portion 16, so as to facilitate the sealing of the empty space 55. Preferably, the empty space 55 should be sealed and with substantially free of fluid communication with its outside. For instance, the air gap 56 with a gap width of about 3 mm to 20 mm would enable a desirable radiantly cooling/heating effect, yet the formation of condensation on the surface of the radiant panel 10 can be suppressed or largely suppressed.

In a more preferred embodiment, the air gap 56 may be fully or partially filled with a thermal conductive layer. The thermal conductive layer may comprise a single or a combination of material. Specifically, the material may be a fluidic material containing a combination of different fluids and/or solids. Alternatively, the fluidic material may contain a mixture of gases, liquids or both. Optionally, the thermal conductive layer may comprise a metallic substance in solid form, such as stainless steel wool or fiber. In another example, a non-metallic graphite material may be used for filling the air gap 56 to serve as a thermal conductive layer. Generally, as shown in Table 1 below, the material used for forming the thermal conductive layer would have a thermal conductivity higher than that of air for achieving an improved radiant cooling effect, while the suppression of condensation on the radiant surface 50 can be maintained at an optimized level.

TABLE 1 Substance Thermal Conductivity (W/m ° C.) Air (gas) 0.0226 W/m ° C. Helium (gas) 0.1411 W/m ° C. Water (liquid) 0.599 W/m ° C. Stainless Steel 304 (solid) 14.4 W/m ° C. Graphite (solid) 5-35 W/m ° C.

On the other hand, both the outer radiant surface 50 and the inner radiant surface 52 should be maintained substantially parallel with each other throughout the entire surface in order to maximize uniformity in heat transfer. The following mathematical relations between the efficiency of radiation heat transfer between two surfaces, i.e., the outer and inner radiant surfaces, with respect to various variables can be defined as, and with reference to FIG. 8 :

Radiation from heat source dA₁ (temperature at T₁) to dA₂ (temperature at T₂):

$\frac{{\sigma cos\Phi}_{1}\cos\Phi_{2}{dA}_{1}{dA}_{2}}{\pi x^{2}}\left( {T_{1}^{4} - T_{2}^{4}} \right)$

where, σ=Stefan-Boltzmann constant=5.67×10⁻⁸ W m⁻² K⁻⁴

-   -   dA₁=surface area of the first radiant surface     -   dA₂=surface area of the second radiant surface     -   x=gap distance apart between surfaces dA₁ and dA₂     -   Φ₁=angle of inclination (between normal of surface and gap         distance) of surface dA₁     -   Φ₂=angle of inclination (between normal of surface and gap         distance) of surface dA₂     -   T₁=surface temperature in K of the first radiant surface dA₁     -   T₂=surface temperature in K of the second radiant surface dA₂

Based on the arrangement of the base panel 30 with respect to the outer housing portion 16, the uniform alignment of the panel sections 32 would be able to maintain the angles of inclination Φ₁ and Φ₂ to a minimum. In an ideal scenario, Φ₁ and Φ₂ should both equal to zero. Advantageously, the present invention as discussed provides a radiant assembly with both the outer and inner radiant surfaces in a substantially straight alignment (where Φ₁ and Φ₂ are close to zero), which effectively minimizes the adverse effects on radiation heat transfer caused by geometric factor according to the Lambert's Cosine Law. The resulted radiation heat transfer from the outer radiant surface 50 (dA₁) to the inner radiant surface 51 (dA₂) of the radiant assembly 10 would be defined as:

$\frac{\sigma{dA}_{1}{dA}_{2}}{\pi x^{2}}\left( {T_{1}^{4} - T_{2}^{4}} \right)$

Advantageously, a coating for enhancing heat transfer performance may be applied on the surface of the inner radiant surface 52, i.e., on the base panel 30, and the internal side 51 of the outer housing portion 16, which serves to facilitate heat transfer between the base panel 30 and the outer housing portion 16. An example of a coating suitable to be used for the present invention would be the thermal dissipation and radiation coating ZS-411 from ZSWH Chemical Co. Ltd. More preferably, a second coating with high enhanced heat transfer performance may be applied on the outer radiant surface 50, i.e., facing the heat source, for more effective suppression of condensation.

The outer housing portion 16 is adapted for coupling with the main housing portion 17 so as to conceal the base panel 30 and the heat transfer pipe 20 therein. As shown, an internal space 57 is formed between the main housing portion 17 and the base panel 30. Preferably, the outer housing portion 16 and the main housing portion 17 can be sealed together by, for instance, applying a sealant 24 along the junction where the two housing portions merge, i.e., along the edges of the coupling flanges 48 of the first housing portion 16. Preferably, a spray-able insulation material, for instance, a polyurethane (PU) foam filler 60, may be used for filling the internal space 57. On the main housing portion 17, an opening (not shown) may be provided for allowing filling of insulation material into the internal space 57. Additional openings may be provided for air to exit as the insulation material 60 occupies the internal space 57, for facilitating the filling process. The PU foam provides an effective insulation to the heat transfer pipe 20 and the base panel 30 from absorbing heat from, or releasing heat to, places other than the radiant surface. Preferably, the PU foam filler 60 would have a density of no less than 48 kg/m³ and able to offer a compression strength of at least 257 kPa. More preferably, the PU foam filler 60 would have a thermal conductivity of 0.0216 W/m° C. rated at 10° C. nominal temperature, for achieving a desirable level of insulation. The PU foam filler 60 is covered by a cladding 62, which may be of a thickness of, say, 0.6 mm.

FIGS. 6 a to 6 j show various views of another embodiment of a cooling/heating assembly according to the present invention, generally designated as 63. The assembly 63 is covered at its top by a cladding 64 of a thickness of, say, 0.6 mm. Below the cladding 64 is a plastic frame 70. An inlet end 65 and an outlet end 66 of a heat transfer tube 67 (which meanders within the assembly 63) extend out of the interior of the assembly 63. The heat transfer tube 67 is affixed to a base panel 68 by a number of plastic belts 69.

The plastic frame 70, base panel 68 are affixed with each other by a number of fastening means, e.g. screws 71, and to the location where the plastic frame 70 and the base panel 68 join each other is applied a sealant 72 to enhance insulation of the assembly 63, in particular the insulation of a separation 73 formed between the base panel 68 and an outer radiant panel 74 from the outside environment. The separation 73 is at least partly filled with a thermal conductive material whose thermal conductivity is higher than that of air, to facilitate heat transfer between the base panel 68 (which is in contact with the heat transfer tube 67) and the outer radiant panel 74. In particular, the thermal conductive material may be graphite. To insulate the heat transfer tube 67 from the outside environment, an insulating material (e.g. polyurethane (PU) foam) 75 is introduced to fill the interior of the assembly 63.

FIGS. 7 a to 7 h show various views of yet another embodiment of a cooling/heating assembly according to the present invention, generally designated as 76. The assembly 76 is covered at its top by a cladding 77 of a thickness of, say, 0.6 mm. Below the cladding 77 is a plastic frame 83. An inlet end 78 and an outlet end 79 of a heat transfer tube 80 (which meanders within the assembly 76) extend out of the interior of the assembly 76 adjacent two opposite sides of the assembly 76 and in two opposite directions.

The plastic frame 83 and a base panel 81 made of a thermal conducting metal or alloy are affixed with each other by a number of fastening means, e.g. screws 84, and to the location where the plastic frame 83 and the base panel 81 join each other is applied a sealant 85 to enhance insulation of the assembly 76, in particular the insulation of a separation 86 formed between the base panel 81 and an outer radiant panel 87 from the outside environment. The separation 86 is at least partly filled with a thermal conductive material whose thermal conductivity is higher than that of air, to facilitate heat transfer between the base panel 81 (which is in contact with the heat transfer tube 80) and the outer radian panel 87. In particular, the thermal conductive material may be graphite. To insulate the heat transfer tube 80 from the outside environment, an insulating material (e.g. polyurethane (PU) foam) 88 is introduced to fill the interior of the assembly 76.

A major difference between the radiant cooling/heating assembly 76 and the previously-discussed embodiments of radiant cooling/heating assemblies is that in the assembly 76, as can be seen in FIGS. 7 b and 7 d , the heat transfer tube 80 is not of a generally circular cross-section, but is of a rectangular cross-section. Thus, both upper surface 89 and lower surface 90 of the heat transfer tube 80 are generally flat. By way of such an arrangement, there is a larger contact area between the heat transfer tube 80 and the base panel 81, thus enhancing the heat transfer between the heat transfer tube 80 and the base panel 81 in this assembly 76.

In the discussion of the following embodiment illustrated in FIGS. 9 a to 9 d and 10, the terms “radiant panel(s)” and “radiant cooling panel(s)” quoted previously will be renamed as “cooling assembly”/“cooling assemblies”. The term “radiant surface(s)” quoted previously will be renamed as “cooling surface(s)”. The term “radiant cooling effect” quoted previously will be renamed as “cooling effect”. Furthermore, the terms “air gap” and “gap” quoted previously will be collectively renamed as “separation”.

FIGS. 9 a to 9 d and 10 illustrate an alternative, i.e., a further embodiment of a cooling/heating assembly/panel according to the present invention, generally designated as 110. Similar to the previous embodiments, the cooling/heating assembly/panel 110 takes the shape of a square or in rectangular form. Dimensions and thickness of the assembly/panel 110 may vary depending on deployment area, manufacturing constraints or other limitations. Although different shapes of the cooling/heating assembly/panel 110 may be adopted for specific constructional implementation, particularly, tileable shapes are preferred for forming an “array” of panels 110 effectively covering a broad ceiling area, floor area or wall area.

As shown in FIGS. 9 a to 9 c , each assembly/panel 110 has a functional side 111 and a non-functional side 112 which is the back side of the panel 110. The functional side 111 provides a substantially flat surface covering the entire area of the panel 110, whilst four lateral sides 113 surround the assembly 110 and define the thickness of the panel 110. The functional side 111, non-functional side 112 and the four lateral sides 113 together define a panel housing 115 for the assembly 110. The panel housing 115 includes an outer housing portion 116 and a main housing portion 117 coupled thereto. Each assembly 110 further includes an inlet end and an outlet end (not shown) for passage of a heat transfer fluid media, such as water. The inlet end provides access to a heat transfer pipe 120 inside the assembly 110 by the fluid media, i.e., chilled water or heated water, which is driven by the connected heat exchanger 102 or boiler 101. The assembly 110 according to the present embodiment provides effective cooling and heating, depending on the temperature of the heat transfer fluid media which runs through the heat transfer pipe 120, while condensation on the cooling surface can be largely suppressed or minimized.

Inside the panel housing 115, a base panel 130 provides general support for the meandering heat transfer pipe 120. For instance, the base panel 130 may be consisted of several elongated rectangular panel sections 132 lying adjacent to each other. Likewise, these panel sections 132 are made from heat conductive metallic material such as aluminum or copper, or any other suitable metal with good heat transfer characteristic. The panel sections 132 may be held together, i.e., side by side. In particular, conducting portions 133 may be provided on each of the panel sections 132 for facilitating direct contact with the heat transfer pipe 120. The general construction of the panel sections 132 and their positional relationship with the heat transfer pipe 120 would be implemented in a similar manner as described in the previous embodiments.

The base panel 130 is bounded by frame members 141 at each of the four lateral sides. The frame members 141 define a peripheral frame 140 for the entire base panel 130. The peripheral frame 140 provides structural rigidity for the base panel 120 against warping or bending. For instance, the frame members 141 may be formed by a thermally insulating material such as nylon or resin. As shown in FIG. 9 d , each of the frame members 141 has a cross-sectional profile of an “L” shape. The frame members 141 further provide support for the sidewalls 114 of the panel housing 115.

The panel housing 115 of the cooling assembly 110 encloses the base panel 130, the heat transfer pipe 120 and the peripheral frame 141. The panel housing 115 includes the outer housing portion 116, and the main housing portion 117 arranged for coupling thereto. Similar to the previous embodiments, an insulation material filler 160, such as polyurethane foam, is used to fill within the panel housing 115. For instance, coupling flanges 118 may be provided around the peripheral edges of the outer housing portion 116 for facilitating the assembling and sealing of the two housing portions 116, 117. The main housing portion 117 is secured to the frame members through fasteners 147, for example, rivets, as shown. An external side of the outer housing portion 116 provides an outer cooling surface 150 substantially covering the entire functional side 111. The base panel 130 includes an inner cooling surface 152 on its underside facing an inner side 151 of the outer housing portion 116. The inner cooling surface 152 of the base panel 130 should ideally be a flat or a substantially flat surface. For instance, the outer housing portion 116 would have a thickness of at least 0.5 mm, although a higher thickness is more preferable. The outer housing portion 116 may have a thickness of up to 3 mm for providing desirable rigidity.

As illustrated in FIG. 9 d , a separation 156, preferably with a uniform separation, is formed between the inner cooling surface 152 and the inner side 151 of the first housing portion 116. The separation 156 would have a constant or substantially constant separation width throughout the width of the cooling assembly 110. Preferably, the separation width would be maintained substantially constant and at a value of 0.3 mm to 20 mm, and more preferably at a value of 0.3 mm to 10 mm.

In particular, one or more substrates made from one or more sheet-like material may be positioned within the separation 156 for acting as a thermal conductive layer. Generally, the material used for forming the thermal conductive layer would have a thermal conductivity higher than that of air for achieving an improved cooling effect, while the suppression of condensation on the cooling surface 150 can be maintained at an optimized level. The substrate within the thermal conductive layer can either be an isotropic or anisotropic media. An isotropic medium, such as cooper and aluminum, provides that its material properties, including thermal conductivity, are uniform and are independent of direction. Whereas an anisotropic medium, such as wood and graphite, refers to a medium in which its material properties are different in all directions. For example, the thermal conductivity of the graphite in the planar direction is about 700 W/mK and the vertical direction is about 35 W/mK. In other words, the material properties of anisotropic materials are dependent upon the orientation of the body of the materials.

According to the present embodiment, a graphite substrate is used as thermal conductive media within the separation 156. The graphite substrate may entirely fill or partially fill the separation 156. Graphite substrate, as an anisotropic media, has a higher thermal conductivity in its planar direction than vertical direction that can evenly and effectively transfer the heat energy from the surface of the radiant cooling panel 110 to the cooling media in the heat transfer pipe 120. Alternatively, one or more additional substrates of a different material than graphite may be used to form the thermal conductive layer within the separation 156. For instance, the thermal conductive layer may consist of a graphite substrate and one or more acoustic layers. Particularly, the one or more acoustic layers could provide acoustic insulation for restricting transfer of sound or sound reverberation within the space where the assembly 110 are installed. The one or more acoustic layers may comprise composite or non-composite material to act as a barrier or an absorber. For instance, the acoustic layer may comprise a substrate made from one or more sheets of non-woven fabric. The assembly 110 provided with one or more acoustic layers could be well suitable for used as perforated ceiling panels or veneer ceiling panels.

A sealing arrangement is provided between the outer housing portion 116 and the main housing portion 117. A silicon sealant 145 may be used to fill slots formed between the coupling flanges 118 i.e., at the four sides, and the main housing portion 117, as shown in FIG. 9 d , such that the silicon sealant seals over the fasteners which secure the main housing portion 117. For instance, a foam sealing member 119 is disposed within the slots and within the silicon sealant for an improved sealing effect.

In the present embodiment, the above arrangement results in a higher overall heat transfer coefficient, thus improving the cooling capacity of the radiant cooling panels 110. A lower surface temperature is achieved on the cooling assembly 110 than on the cooling assembly 10 according to the previous embodiments. FIG. 10 shows an infrared image taken on the assembly 110 according to the present embodiment. As shown, thermal uniformity throughout the cooling surfaces of the assembly 110 is proven to be exceptional, and has improved over the previous embodiments.

In the discussion of the following embodiments illustrated in FIGS. 11 a to 11 f and 12 a to 12 f , the terms “radiant panel(s)” and “radiant cooling panel(s)” quoted previously will be renamed as “cooling/heating assembly”/“cooling/heating assemblies”. The term “radiant surface(s)” quoted previously will be renamed as “cooling/heating surface(s)”. The term “radiant cooling effect” quoted previously will be renamed as “cooling/heating effect”. Furthermore, the terms “air gap” and “gap” quoted previously will also be collectively renamed as “separation”.

FIGS. 11 a to 11 f illustrate a yet further embodiment of a cooling/heating assembly 200 according to the present invention, and FIGS. 12 a to 12 f illustrate a still further embodiment of a cooling/heating assembly 300 according to the present invention.

Referring firstly to FIGS. 11 a to 11 f , and similar to the previous embodiments, the cooling/heating assembly 200 takes the shape of a square or in rectangular form. Dimensions and thickness of the assembly 200 may vary depending on deployment area, manufacturing constraints or other limitations. Although different shapes of the cooling assembly 200 may be adopted for specific constructional implementation, particularly, tileable shapes are preferred for forming an “array” of the cooling/heating assemblies 200 effectively covering a broad ceiling area, floor area or wall area.

A significant difference between the cooling/heating assembly 200 of the present embodiment on the one hand and the radiant panels 10 and the cooling assembly 110 according to the previously-discussed embodiments on the other hand is that the cooling/heating assembly 200 has two oppositely-facing functional sides 212 a, 212 b, each including an outer cooling/heating surface 213 a, 213 b exposed to the outside environment for carrying out heat transfer between the cooling/heating assembly 200 and the outside environment. In particular, the two outer cooling/heating surfaces 213 a, 213 b of the functional sides 212 a, 212 b face away from each other. It is also envisaged that the cooling/heating assembly 200 can provide both cooling effect and heating effect, in a manner to be discussed below.

Each of the outer cooling/heating surfaces 213 a, 213 b of the respective functional sides 212 a, 212 b provides a substantially flat surface covering the entire area of the cooling/heating assembly 200, whilst four lateral sides 214 surround the cooling/heating assembly 200 and define the thickness of the assembly 200. The functional sides 212 a, 212 b and the four lateral sides 214 together define an assembly housing 216 for the cooling/heating assembly 200. The assembly housing 216 includes an outer housing portion 218 and a main housing portion 220 coupled thereto. Each cooling/heating assembly 200 further includes an inlet end 222 and an outlet end 224 for passage of a heat transfer fluid media, such as water. The inlet end 222 provides access to a meandering heat transfer pipe 226 (which may be made of a metal or alloy with good heat transfer characteristic, such as copper, and may be of a diameter of, say, 12 mm) inside the cooling/heating assembly 200 by the heat transfer fluid media, e.g., water, which is driven by the connected heat exchanger 102 or boiler 101. The heat transfer fluid media may also leave the assembly 200 through the outlet end 224. The cooling/heating assembly 200 according to the present embodiment provides effective cooling and heating while condensation on the cooling surface can be largely suppressed or minimized.

The cooling/heating assembly 200, when providing cooling effect, may, for example, be deployed in enclosed areas in which high temperature is undesirable, e.g. data centers, in particular amongst server rack cabinets. It is known that hundreds or even thousands of continuously operating servers may be housed in a data center, thus generating immense heat, which would adversely affect the operation of the servers. The cooling/heating assemblies 200 may therefore be installed amongst the server rack cabinets in data centers to absorb heat generated by the servers, thus lowering the temperature, or at least hindering the increase in temperature, in the data centers.

In addition to providing cooling effect, the cooling/heating assembly 200 can also provide heating effect. In particular, by passing hot heat transfer fluid media, e.g. heated water, through the heat transfer pipe 226, heat energy in the hot heat transfer fluid media may be released from the hot heat transfer fluid media through both of the oppositely-facing functional sides 212 a, 212 b of the cooling/heating assembly 200 by radiation to the space where the cooling/heating assembly 200 is installed.

The two functional sides 212 a, 212 b comprise two parallel outer panels 228 each made of an ideally flat or substantially flat metal or alloy with good heat transfer characteristic, such as aluminum, and may each be of a thickness of, say, 1.2 mm. The heat transfer pipe 226 is secured in position between the two outer panels 228 by two oppositely facing inner panels 230 made of an ideally flat or substantially flat metal or alloy with good heat transfer characteristic, such as aluminum, and may be of a thickness of, say, 0.8 mm. The two inner panels 230 are inner of the two outer panels 228, i.e. the distance between the heat transfer pipe 226 and each inner panel 230 is shorter than that between the heat transfer pipe 226 and each outer panel 228. The two outer panels 228 and the two inner panels 230 are substantially parallel to one another.

On an inner side 232 (i.e. the side facing the heat transfer pipe 226) of each of the inner panels 230 is formed a number of elongate troughs 234 of a generally C-shaped cross-section. When the two inner panels 230 are duly assembled with each other, the troughs 234 face each other to form a number of generally cylindrical tubes each for receiving one of a number of straight sections of the heat transfer pipe 226 in the cooling/heating assembly 200, so as to secure the heat transfer pipe 226 in place in the cooling/heating assembly 200. Fastening means (e.g. screws, rivets, straps, and the like) may be further provided to secure the heat transfer pipe 226 to the cooling/heating assembly 200. By way of such an arrangement, the heat transfer pipe 226 and the inner panels 230 are in physical contact with each other, and are thus in a heat transferrable relationship with each other.

Between each pair of the inner panel 230 and the outer panel 228 which are adjacent to each other is a separation 236 of, preferably, a thickness of 0.3 mm to 10 mm which is partially or fully filled with a thermal conductive media, such as a layer of graphite, such as an anisotropic graphite sheet 238, of a thickness of, say, 0.5 mm. The separation 236 is preferably a uniform separation with a constant or substantially constant separation width throughout the span of the cooling/heating assembly 200. Alternatively, one or more additional substrates of a different material than graphite may be used to form the thermal conductive layer within the separation 236. For instance, the thermal conductive layer may consist of a graphite substrate and one or more acoustic layers. Particularly, the one or more acoustic layers could provide acoustic insulation for restricting transfer of sound or sound reverberation within the space where the cooling/heating assemblies 200 are installed. The one or more acoustic layers may comprise composite or non-composite material to act as a barrier or an absorber. For instance, the acoustic layer may comprise a substrate made from one or more sheets of non-woven fabric.

Preferably, a spray-able insulation material, for instance, a polyurethane (PU) foam filler 242, may be used for filling an internal space 244 between the two inner panels 230 not otherwise occupied by the heat transfer pipe 226. The PU foam 242 provides an effective insulation to the heat transfer pipe 226 and inner panels 230 from absorbing heat from, or releasing heat to, places other than the radiant surfaces. Preferably, the PU foam filler 242 would have a density of no less than 48 kg/m 3 and be able to offer a compression strength of at least 257 kPa. More preferably, the PU foam filler 242 would have a thermal conductivity of 0.0216 W/m° C. rated at 10° C. nominal temperature, for achieving a desirable level of insulation.

In particular, one or more substrates made from one or more sheet-like material may be positioned within the separation 236 for acting as a thermal conductive layer. Generally, the material used for forming the thermal conductive layer would have a thermal conductivity higher than that of air for achieving an improved cooling effect, while the suppression of condensation on the outer cooling/heating surfaces 212 a, 212 b can be maintained at an optimized level. The substrate within the thermal conductive layer can either be an isotropic or anisotropic media. An isotropic medium, such as cooper and aluminum, provides that its material properties, including thermal conductivity, are uniform and are independent of direction. Whereas an anisotropic medium, such as wood and graphite, refers to a medium in which its material properties are different in all directions. For example, the thermal conductivity of the graphite in the planar direction is about 700 W/mK and the vertical direction is about 35 W/mK. In other words, the material properties of anisotropic materials are dependent upon the orientation of the body of the materials.

According to the present embodiment, the graphite sheet 238 is used as a thermal conductive media within the separation 236. The graphite sheet 238 may entirely fill or partially fill the separation 236. Alternatively, or in addition, one or more additional substrates of a different material than graphite may be used to form the thermal conductive layer within the separation 236. For instance, the thermal conductive layer may include, in addition to the graphite sheet, one or more acoustic layers. Particularly, the one or more acoustic layers could provide acoustic insulation for restricting transfer of sound or sound reverberation within the space where the cooling/heating assembly 200 are installed. The one or more acoustic layers may comprise composite or non-composite material to act as a barrier or an absorber. For instance, the acoustic layer may comprise a substrate made from one or more sheets of non-woven fabric. The cooling/heating assembly 200 provided with one or more acoustic layers could be well suitable for used as perforated ceiling panels or veneer ceiling panels.

Referring now to FIGS. 12 a to 12 f , and similar to the previous embodiments, the cooling/heating assembly 300 takes the shape of a square or in rectangular form. Dimensions and thickness of the assembly 300 may vary depending on deployment area, manufacturing constraints or other limitations. Although different shapes of the cooling assembly 300 may be adopted for specific constructional implementation, particularly, tileable shapes are preferred for forming an “array” of the cooling/heating assemblies 300 effectively covering a broad ceiling area, floor area or wall area.

Similar to the cooling/heating assembly 200 described above, the cooling/heating assembly 300 also has two oppositely-facing functional sides 312 a, 312 b, each including an outer cooling/heating surface 313 a, 313 b exposed to the outside environment for carrying out heat transfer between the cooling/heating assembly 300 and the space in which the cooling/heating assembly 300 is installed. In particular, the outer cooling/heating surfaces 313 a, 313 b face away from each other. It is also envisaged that the cooling/heating assembly 300 can provide both cooling effect and heating effect, depending on the temperature of a heat transfer fluid media, e.g. water, which runs through a heat transfer pipe 316 which meanders in an internal space 317 of an assembly body 318 of the cooling/heating assembly 300. The heat transfer fluid media, e.g. water, enters the heat transfer pipe 316 via an inlet end 320 and exits the heat transfer pipe 316 via an outlet end 322. If chilled water is caused to pass through the heat transfer pipe 316, the cooling/heating assembly 300 is intended to provide cooling effect, whereas if heated hot water is caused to pass through the heat transfer pipe 316, the cooling/heating assembly 300 can provide heating effect.

The cooling/heating assembly 300 has two outer panels 324 each made of a sheet of metal or alloy with good heat transfer characteristic, such as aluminum, and of a thickness of, say, 1.2 mm. The outer surfaces of the outer panels 324 are the cooling/heating surfaces 313 a, 313 b. The heat transfer pipe 316 is secured within the internal space 317 of the assembly body 318 between the two outer panels 324 by two oppositely facing inner panels 326 which are also each made of a sheet of metal or alloy with good heat transfer characteristic, such as aluminum, and of a thickness of, say, 0.8 mm. The distance between the heat transfer pipe 316 and the inner panels 326 is shorter than that between the heat transfer pipe 316 and the outer panels 324. The heat transfer pipe 316 and the inner panels 326 are in physical contact with each other, and are thus in a heat transferrable relation with each other.

Preferably, a spray-able insulation material, for instance, a polyurethane (PU) foam filler 328, may be used for filling an internal space 317 between the two inner panels 326 not otherwise occupied by the heat transfer pipe 316. The PU foam 328 provides an effective insulation to the heat transfer pipe 316 and inner panels 326 from absorbing heat from, or releasing heat to, places other than the radiant surfaces. Preferably, the PU foam filler 328 would have a density of no less than 48 kg/m³ and be able to offer a compression strength of at least 257 kPa. More preferably, the PU foam filler 328 would have a thermal conductivity of W/m° C. rated at 10° C. nominal temperature, for achieving a desirable level of insulation.

Between each pair of the inner panel 326 and the outer panel 324 which are adjacent to each other is a separation 332 of, preferably, a thickness of 0.3 mm to 10 mm which is partially or fully filled with a thermal conductive media. The separation 332 is preferably a uniform separation with a constant or substantially constant separation width throughout the width of the cooling/heating assembly 300.

A significant difference between the cooling/heating assembly 300 of the present embodiment and the cooling/heating assembly 200 discussed above is that in the assembly 300, a graphite coating 330 is used as a thermal conductive media within the separation 332 between each pair of the inner panel 326 and the outer panel 324. The graphite coating 330 may entirely fill or partially fill the separations 332. Alternatively, or in addition, one or more additional substrates of a different material than graphite may be used to form the thermal conductive layer within the separation 332. For instance, the thermal conductive layer may include, in addition to the graphite coating and/or thermal conductive substrate, one or more acoustic layers. Particularly, the one or more acoustic layers could provide acoustic insulation for restricting transfer of sound or sound reverberation within the space where the cooling/heating assembly 300 are installed. The one or more acoustic layers may comprise composite or non-composite material to act as a barrier or an absorber. For instance, the acoustic layer may comprise a substrate made from one or more sheets of non-woven fabric. The cooling/heating assembly 300 provided with one or more acoustic layers could be well suitable for used as perforated ceiling panels or veneer ceiling panels.

It should be understood that the above only illustrates and describes examples whereby the present invention may be carried out, and that modifications and/or alterations may be made thereto without departing from the spirit of the invention.

It should also be understood that certain features of the invention, which are, for clarity, described in the context of separate embodiments, may also be provided in combination in a single embodiment. Conversely, various features of the invention which are, for brevity, described in the context of a single embodiment, may also be provided separately, or in any suitable sub-combination. Although the specification is described in terms of embodiments, not every embodiment includes only a single technical solution. This description of the specification is merely for the sake of clarity. Those skilled in the art should regard the specification as a whole, and the technical solutions in the embodiments can also be combined appropriately to form other embodiments that can be understood by those skilled in the art.

All references specifically cited herein are hereby incorporated by reference in their entireties. However, the citation or incorporation of such a reference is not necessarily an admission as to its appropriateness, citability, and/or availability as prior art to/against the present invention. 

1. A radiant cooling and/or heating assembly comprising: a housing containing a heat transfer pipe through which a heat transfer medium is passable, at least one outer radiant heat transfer surface for heat transfer with the surrounding environment, a first heat transfer panel with a first inner heat transfer surface, and a second heat transfer panel with a second inner heat transfer surface which faces said first inner heat transfer surface of said first heat transfer panel, wherein said first heat transfer panel is in contact with at least part of said heat transfer pipe, wherein said first inner heat transfer surface and said second inner heat transfer surface are separated from each other by a separation, and wherein said separation is filled at least partly with a thermal conductive layer made of at least one material having a thermal conductivity higher than that of air.
 2. The assembly of claim 1, wherein said separation is substantially sealed against outside fluid communication.
 3. The assembly of claim 1, wherein said separation is of a substantially constant gap width.
 4. The assembly of claim 3, wherein said separation is of a gap width of 0.3 mm to 20 mm.
 5. The assembly of claim 1, wherein said at least one material is solid graphite.
 6. The assembly of claim 1, wherein said thermal conductive layer comprises at least an anisotropic graphite sheet.
 7. The assembly of claim 1, wherein said thermal conductive layer comprises at least a graphite coating.
 8. The assembly of claim 1, wherein said separation includes at least one acoustic layer to act as a sound barrier or absorber.
 9. The assembly of claim 1, wherein said heat transfer pipe meanders within said housing.
 10. The assembly of claim 1, wherein said first heat transfer panel comprises a plurality of heat conductive metal or alloy panel sections lying adjacent to each other.
 11. The assembly of claim 10, wherein each panel section of said panel sections includes a heat conducting portion with a concave surface having a curvature complementary to a curvature of an outer surface of said heat transfer pipe.
 12. The assembly of claim 11, wherein said heat conducting portion of said panel section is c-shaped or semi-circular in shape.
 13. The assembly of claim 12, wherein two adjacent panel sections with oppositely arranged conducting portions surround said heat transfer pipe and substantially cover an entire straight portion of said heat transfer pipe.
 14. The assembly of claim 1, wherein said assembly includes at least two outer radiant heat transfer surfaces for heat transfer with the surrounding environment.
 15. The assembly of claim 14, wherein said at least two outer radiant heat transfer surfaces face opposite directions.
 16. The assembly of claim 1, wherein said heat transfer pipe is of a rectangular cross-section.
 17. A cooling and/or heating system including a heat exchanger and/or a boiler connected with at least one radiant cooling and/or heating assembly according to claim
 1. 18. The system according to claim 17, wherein said at least one radiant cooling and/or heating assembly comprises a plurality of radiant cooling and/or heating assemblies. 